Apparatus for generating infra-red rays



June 4, 1929. T BARRETT 1,715,634

APPARATUS FOR GENERATING INFRA-RED RAYS Filed Sept. 23, 1926 I 3 INVENTOR.

Thomas J B rr Wo n Low A TTORNE Y5.

PATENT OFFICE.

THOMAS J. BARRETT, OF LOS ANGELES, CALIFORNIA.

APPARATUS FOR GENERATING I NFRA-RED RAYS.

Application filed September This invention relates to therapeutics, and more particularly to a new apparatus for generating and applying infra-red rays in the treatment of diseases of the human, or other bodies.

The solar spectrum is composed of certain forms of energy, manifested by wave lengths of varying lengths. 80 per cent of the energy is known as infra-red energy. The infra-red is below the point of visibility to the human eye. 13 per cent of the energy comes within the range of the hmnan eye and is known as light. Seven per cent of the energy is the extremely short wave. lengths, invisible to the human eye and known as ultra-violet. The infra-red energy is composed of the very long invisible waves. The ultra-violet is composed of the very short invisible rays.

Certain substances radiate infra-red rays when heated. The particular wave length of infra-red rays given off depends uponthe 7 temperature of the radiating body. At low temperatures the energy given off is the extremely long waves. As the temperature of the radiating body is increased, the wave length of the energy decreases.

A peculiarity of the infra-red is that it is iven oil in greater volume by a black body. lack iron will give off a greater volume than gray iron. Black copper will give off a greater volume than burnished copper.

The volume of infra-red ray energy depends upon the extent of the surface of the radiating element. If the surface of the radiating element is small, the volume of infrared energy will be small. If the area of ra diating surface is large the volume of infrared my energy will be large.

In other infra-red generators, the source of the energy has been the surface of the heating element itself. In the present appara tus, the source of the infra-red energy is the surface of the radiating element. In other forms of generators, the energy is all taken from the field of visible light, at a constant temperature of high degree. The volume of infra-red is thus a negligible quantity and also a very narrow band of energy of extremely short wave lengths. In the present apparatus, we have a radiating element of several hundred square inches, the element being heated from a mild temperature of about 212 degrees in parts of its surface to about 800 degrees in other parts. We thus secure a'wide range of energy, both the long 23, 926. Serial No. 137,353.

waves and the short waves all well within the lield of infra-red.

The general object of the invention is to provide a simple and improved apparatus for generating infra-red rays of varying wave lengths and in greater volume than heretofore, and also an apparatus that is of such a design as to make it convenient and practicable to apply such rays to the human, or other bodies, for therapeutic purposes. I

A more particular object is to provide an apparatus of the character stated, in which heat is applied to a plate of suitable material, such as copper or iron, externally of the radiating surface thereof, so that said plate will give off infra-red rays of varying wave lengths and in greater volume than otherwise, from its radiating surface, for application in. the treatment of diseases. thus enabling the patient to receive on the surface of the body the greatest possible volume of said i ni' ra-red rays.

lVith the above and other objects in view, the invention consists in the novel and useful provision, formation, association, construc tiou, and relative arrangement'of parts, members and features, all as disclosed in the aecompanying drawing, described generally, and-more particularly pointed out in claims.

In the drawing:

Figure 1 is a side elevation of the invention illustrating how it is applied to a patient lying on a table; and,

Figure 2 is a view of the invention on. a large scale, shown partly in elevation and partly in section.

Corresponding parts in both figures are designated by the same reference characters.

The invention includes a semi-spherical hood A formed with an inner radiating wall 1, an outer wall 2,,spaced outwardly from said inner wall, and a cupola a upstanding centrally from the top of said outer wall, 'there being a heating element B interposed between said inner and outer walls extending upwardly from the lower edge of the hood A slightly over one-half the height of the hood. The outer wall 2 is formed at its lower edge with an external flange 3 against which engages an external flange 4 on the lower edge of the inner wall 1, therebeing an upstanding flange 5 on the outer edge of the flange 4 which extends upwardly over the outer edge of the flange 3. A gasket 6 rests upon the flange 3 and a clamp'ri'ng 7 extends over the flanges 4 and 5 and over the gasket Land eni ages the lower si of i and the upper side of said gasket, whereby the flanges 3 and 4 and said gasket are clamped together and the walls 1 and 2 firmly secured together at their lower edges.

The heating element B comprises an electrical coil of wireb which extends externally of the radiating wall 1 in the space 8 between said walland the outer wall 2, the strands of said coil being spaced apart and extending through blocks 9 of insulation fitted in arouate channel irons 10 secured on the outer side of the reflecting wall 1 at suitable distances apart. A clamp band 11 extends around the lower ends of the channel irons 10 and clamps said ends against the wall 1 while a wire 12 with its ends twisted together .at 13 extends around the upper ends of said channel irons and holds said ends against said wall.

' througlr the outerw'all 2 and through a plate. I r 13 of insulation on top of said wall within the cupola a. The ends 19 and'20 of the hcat "The outer wall of the hood A is impressed outwardly at the top at 14 to receive a block 15 of insulationwhich is secured in said im pressionby bindingposts 16 and 17 extending ing' coil 6 are connected to the lower ends of the binding'posts 16 and 17 respectively' in the block 15 which is grooved at 21 to receive said ends of the coil. Leads 22 and 23 are respec tively-connectedto the binding'posts 16 and I 17 and extend upwardlythrough the cupola a to the poles respectively of a generator G.

The s ace- 8 between the walls 1 and 2 is packe with a heat insulating material-E external to heating element B, which conserves the heat within the space between the walls 1 and 2, thus bringing the copper dome up to the efiective temperature for the radiating of the greatest possible volume of infra-red trays, said temperature being desirably from 250 degrees Fah. to approximately 800 degrees -Fah., the heat insulating material placddexternally to the heating element thus enabling the use of a smaller amount of electrical energy in generating an effective heat in the radiating element and making it more economical in operation. The outer wall consists of aluminum, or other suitable metal or material. The'purpose of this wall is to lend an elegant appearance to the apparatus, protect the internal parts and specifically to furnish a 1 backing for the heat insulating material and a The weight 25 balances thehood in any posi convenient part for the suspension of the apparatus in any desired way.

" The top of the cupola a is connected to one end of a rope 24 which extends through an ad;

just'able bracket C and is'connected at its other end to a weight 25. The bracket C is mounted on a wall to be adjusted so that'the hood A maybe let down over different parts of'the body of a patient P lying on a table D.

'tion inwhich it may be lowered. v

The lowerportion of the wall 1 which is heated directly by the coil B gives ofl infrared rays of shorter wave length than the upper portion ofsaid wall which is heated only indirectly by the coil by conduction and convexion, thus enabling the wall 1 to radiate infra-red rays of varying lengths correspond ing substantially to the radiation of such rays by the sun which have great therapeutic value.

The concavity of the wall 1 gives the wall a much greater radiating area. than a flat plate corresponding in area to the area of the internal base of the hood A. Infra-red rays are given ofi' entirely according to the surface area of the radiating element; therefore the dome-shaped element affords the greatest area practicable in a treat-ing apparatus for generating the infrared rays.

The inner wall 1- is made of a suitable metal, or material, such as copper orviron. Copper has a special advantage in this respect: Infra-red rays are given OK in greater volume from ablack substance... By heating the' copper to an annealing temperature, it

turns black. In this manner we have not only a substance which gives off infra-redrays efiicicntly, but We also have the desirable black body, which in other equipments may. be secured by use of black paint or enamel... f

,It is obvious, that various v ch an ges, modifications and variations. may be made intpracticing the invention, indeparture from the 1 particular showing of the drawing, without departing from the true spirit of the invention. I

Having thus disclosed my invention, I claim and desire to secure by Letters Patent: 1. In an apparatus as'de'scribed, a conc avoconvex metal plate for radiating infra-red rays, and a heating element on the convex side of said plate for directly heating said plate only a portion of its area for enabling the plate to radiate infra-red raysof varying W2].V0 lengths from its concaved surface.

and a packing of heat insulating material between said walls.

' 4.1m an apparatus as described, domeshaped wall, and an electric heating coil surrounding the lower portion of said wall for causing said wallv to generate infra-red rays of diiferent wave lengths.

In testimony whereof, I have signed my name.

" V THOMAS J. BARRETT. 

